Sewing machine and method of sewing



Jan. 1, 1952 T. A. B'RAMFITT ETAL SEWING MACHINE AND METHOD OF SEWING 3 Sheets-Sheet 1 Filed April 18, 1947 INVENTORS w' Jan. 1, 1952 'r. A. BRAMFITT EI'AL SEWING MACHINE AND METHOD OF SEWING 3 Sheets-Sheet Filed April 18, 1947 I VENTORS Jan. 1, 1952 T. A. BRAMFITT ETAL SEWING MACHINE AND METHOD OF SEWING 5 Sheets-Sheet 3 Filed April 18, 1947 I be employed "with Patented Jan. 1, 1952 assoc 24 v INE ANDJMETIHOD F SEWING I Thomas A. Brai'nfitg, Watervliet, and Edward 0.

of- New York N. Y., gassignorsuto Cl'uett,

Eroy, N. Y.,a corporation which threadsarepassed back and'forth through the fabridlayers repeatedly. In -'ord'erto obtain a satisfactory output of garments so made, it is necessarythat the sewing machines be operated ata high speed and to obtain such speeds it ha'sheen necessary to keep the thread fairly taut. "The-thread of the stitch istherefore uneer tension and when a. garment sewed in this manner is subsequently laundered, the thread itself "shrinks and causes a furthershrinkage-o'r 'compres on and often *puckering', of the fabric.

This additional shrinkage and puckering isfvery pronounced when several rows of stitching are placed fairly close together Within a relatively small -strip of fabric, such-as in the-making of seams, collars and neckban'ds. -E'fforts have been made to-eliminate this additional shrinkage -by using-a thread which is substantially non-shrinking, but as yet no satisfactory non-shrinking thread for this purpose has been discovered.

An object of this invention is to'provide "an improved. method of and apparatus for sewing, with --which this additional shrinkage and puckeri'ng of the fabric-or layers united by the stitching is substantially eliminated, :even when .using ordinar'ywhread; 'with which the sewing may: be performed at the same rate and in the same manner as heretofore.

Another object of this invention is to provide improved method of sewing, with which a s in the thread, of the completed stitch may be obtained automatically; with which the sewing operation maybe performed at the usual or high speeds; which may stitches varying considerably in size; withwhich the'slacknessf in thestitches may be uniformly distributed; and which Will be relatively simple. V

Another object of the invention is to'fprbvicle improved mechanism for sewing, 'withwhich the tension or the thread incorporated in'a line 6f stitching is controlled; "with which a de'siie'd hedesired degree of slacknes gree of slackn'es's in the threa dofa completed stitch may beobtained, irrespective of the speed at which thestitchjisiformed; with which the :sl'acknessin the-thread -ivill.,be uniform :alo'n'g .positions which will be of Fig. 1'; 5

:the completed stitching; with which the length of .the individual stitches may be varied considerably as usual in sewing machines; with which a minimum modification of existing types of isewing machines will be required; with which 1110 iadditionalimanipulation by the machine op- :erator is required; and which will be. relatively simple, practical, compact and inexpensive.

Various-other objects and advantages will be apparent from the following description of one -.exampleof apparatus formed inaccordance with the invention, and the novel features will be .particularly pointed out hereinafterin connection with "the appended claims.

:In the accompanying drawings:

Fig. 1.:i's an elevation, with a few parts broken away, ofzpart of a. sewing machine constructed in accordance with this invention, certain parts vof the machine being shown in intermediate described more fully hereinafter;

"Fig, 2 is another elevation of the same, the view being at approximately a right angle to that Fig.3 is an elevation of the lower part of the mechanism shown in Fig. 2. but at the opposite side of the mechanism;

Fig. 4 is an elevation ofcertain parts of the mechanism of Fig. 2, in one operative position;

Fig. 5 is a similar view,.but with the parts shown different relative operating positions;

.Fig. dis a sideelevation, on a larger scale, of .parts o'f the machine in the-act of -,sewing, but with the presser foot and throat plate omitted;

Fig. 7 isaQfront-or face elevationof the parts shown .in Fig. '6, but with the presser foot in position; I v

Fig. 8 is a sectional plan of the parts shown in Fig 7, this sectionbeing taken approximately along the line 8- -8 of Fig. 7; and

Fig. 911's an elevation of certain separated from, each other.

jInthe "illustrated e1 nbodiment of the inventlOll', the sewing inachine is a standard type of the parts fe .inema h n fhavifie a a ol which atone jendfhl, ms "a. vertically disposed needle bar. 2 for endwise reciprocation in the usual manner.

. Removably mounted in the lower end of the needle bar 2 is .a needle 3, the upper end of needle 3 entering a recess in the lower end of the needle bar and being secured therein by a.-;.s c e st.. l w end r on o the ;ne ed1e;;has a thread eye 5,through which one of the sewing threads is passed or threaded as usual in sewing machines.

Also mounted on the head I. adjacent the needle bar 2, is a presser foot bar 6, which is yieldingly urged downwardly by a helical compression spring 1. A presser foot member 8 is fitted over the lower end of the bar 6 and it is secured removably thereon by a set screw 9 which is threaded into the side of the lower end portion of the presser foot bar 6. The shank of the screw 9 is received in a slot H] in the upper edge of one side of the member 8, and the head of the screw 9 overlaps the outer face of member 8 so that when the screw is tightened it will clamp the member 8 to the bar 9 in a manner to form a depending extension thereof. This member 8 has a forwardly extending foot II, with a slot |2 extending from the free end of the foot H and beneath the lower end of the needle 3. The upper face of the foot H is provided with a recess |3 which becomes progressively deeper from the side edges towards the inner end of the slot |2 as shown clearly in section in Figure 7.

The machine also has the usual throat plate l4 beneath the presser foot and needle, and feed dogs l5 pass upwardly through throats in the plate l4 and also beneath the presser foot so that fabric disposed on the throat plate I4 and beneath the presser foot may be fed along by small increments through the movement of the dogs I5. This is the usual work feeding mechanism on sewing machines and a thread from the usual shuttle or bobbin (not shown but beneath the throat plate) passes upwardly through the throat plate as usual in sewing machines. The dogs l5 are given a feeding movement in timed relation to the vertical movements of the needle, so that the fabric will be fed along by increments only while the needle is above the fabric.

The member 8 on the lower end of the presser bar 6 rotatably mounts a shaft IS with its axis horizontal or parallel to the upper face of the throat plate. The forward end of the shaft l6 carries a head I! that contains a recess IS in its forward or end face. (See Figs. 1 and 6.) The recess I8 is open along its bottom edge. A pintle l9 extends across the recess I8 (see Fig. '7) between the opposite sides of the head I! having the recess l8. Rockably and individually mounted on the pintle l9 are two blocks 20 and 2| disposed side by side. A wire-like finger or interponent 22 is removably secured at one end to the block 20 so as to form a downwardly depending extension thereof, and this finger 22 then extends into the recess |3 in the upper face of foot II and also forwardly toward the needle. At its forward end finger 22 extends in a direction cross-wise of the slot |2 as shown in Figure '7.

A similar finger 23 depends from the block 2|, except that the finger 23 extends toward the finger 22 and the latter at its free end extends toward the finger 23. A torsion spring 24 has a looped part 25 intermediate of its ends, which part is disposed on one extending end of the pintle l9. One end 26 (Fig. 6) of the spring 24 is anchored to the head H and the other arm 2'! of the spring 24 extends in front of and abuts against the finger 22. This spring 24 urges the block 20 yieldingly in a direction to carry the lower end of the block away from needle 3. A similar torsion spring 28 is mounted on the other extending end of the pintle l9, with one end anchored to the head l1 and the other end extending toward and in front of the anchored end of the finger 23, so that the spring 28 will urge the block 2| at its lower end in a direction away from the needle 3.

The block 20 at its upper end, and adjacent the block 2|, is provided with a beveled cam face 29. This cam face 29 becomes progressively deeper from the front face toward the side edge which is nearer to block 2|, and the block 2| has a similar beveled cam face 39 which becomes deeper from the front face of the block as it progresses toward the block 23. Thus the cam faces 29 and 30 extend from adjoining edges and are aligned in a direction parallel to the axis of the pintle IS.

A metal stamping 3|, Figs. 1 and 6, is secured to the front face of the member 8 above the head l1, and it extends forwardly above the head l1 and then downwardly in front of it, as an angular end 32. This end 32 has a concave seat 33 in its under-face, facing the blocks 20 and 2|, and in this seat 33 is confined a ball 34. The ball 34 rides on both beveled faces 29 and 30 when the head I1 is in a mid-rocking position, that is, the position of the parts as shown in Fig. 1, and since the ball 34 is then received in the deepest parts of the recesses formed by the bevel faces 23 and 30, the springs 24 and 28 will urge both of the members 29 and 2| in a direction to carry the fingers 22 or 23 away from the path of the needle as shown in Fig. 1. The same position of the parts is shown in Fi 3.

If now the shaft I9 is rotated in either direction from the mid position shown in Figs. 1, 2 and 3, the ball 34 will ride up one or the other of the beveled faces 29 and 30, and cam rearwardly the upper end of the block having the face that is engaged by the ball which serves to elevate the depending finger carried by that block. For example, if the shaft I6 is rocked from the mid-position shown in Figs. 1 to 3 in one direction, such as to the position shown in Fig. 7, the beveled face 39 will act as a cam and since the ball is held against displacement this will force rearwardly the upper end of the block 2| and move the finger 23 forwardly into a position close to, but just in the rear of the needle, as shown in Fig. 6. The rocking of shaft l6 also carried finger 23 to one side of the slot l2 in the presser foot. This tensions or stresses the spring 28. At the same time that the shaft |B rocked in that direction into the position shown in Fig. 7, the finger 22 on the block 20 moved into a position across the slot |2 so as to bridge it as shown in Fig. '7.

A stop plate 35 is secured to the member 8 and carries spaced stop edges 36 and 31, Fig. '7, that are alternately engaged by abutments on the head H to limit this rocking movement of the shaft |6 in both directions. When the shaft I6 is rocked in the other direction into the other extreme position, the ball 34 will leave the beveled face 30 and will then be engaged by the beveled face 29. Thus during this rocking of the shaft IS, the beveled face 30 will move away from the ball so that the spring 28 will then urge the lower end of the member 2| yieldingly in a direction to carry the finger 23 in a direction along the line of the sewing, and the beveled or cam face 29 will be engaged by the ball 34 which serves to rock the block 20 in a direction to carry finger 22 forwardly and to one side of the slot It. mo ement is limited by th st p plate 35.

The sha 1. extends throu h the member in which it is r tatab y mounted d ec io (Fig. 1) parallel to the direction of feed of the fabric, a so in a dir i n aw y f om. he needle 3- t the oppos face of h memb r e. shaft l6 carries a member 38 (Figs. 1 and 9), which. is ixed the eon in a su table. manner such as by set screw 39. Disposed on shaft 16 e en the memb 33 and e mber 3 is cam 40, against which the member 38 abuts. This cam 44) is generally cylindrical. but pro-. vided n a e e the w t a no chv 4 (Fi s and which receives a tongue 42 (Figs. 1 and 9. carr o th abut fa e the member 58 a d. which prov es. dr ing qoe s ti between the member 38 and the earn 40. Thecam 40 is provided with a passage 43 from end tags. to end. fac that term a es i! qu s on @PQW? shaft 16 at approximately diametrically opposite, sides of the shaft IS. The cam 40 has a central aperture 44 through which the shaft l6 passes. That wall of the passage 43 nearest to the outside circumference is arcuate with a cent r of curvature at the center'of the passage 44. The opposite or inner margin of the passage 43 is generally V-shaped as at 45, with the center of the V approximately midwayv between the terminals or limits of the passage 43.

An arm 46, Fig. l, is provided at one end with a boss 47, which has acentra-l passage 48 that is fitted over the lower end of the needle bar 2. A set screw 49 in the boss 41 engagesv the bar 2 and secures the arm 46 removably to the'needle. bar for Vertical reciprocation therewith, yet the arm may. be adjusted to a limited extent along the needle. bar. The arm 46 extends to one side of and clears the pressenmember 6, and at its other end it is apertured to. receive the threaded end 55 of a post 51. Nuts 52 are threaded on the end 54 at opposite sides of the arm 46, so thatwhen the nuts 52 are tightened against the. arm 46. they will secure the'post 5| rigidly but adjust: ably. to the arm 46 in a position to extendupwardly from arm 46, as shown in Fig. 1. The post 5! above the threaded end 50 is preferably made square or,"rectangula r in transverse cross-1 section, 'and a, runner or shoe 53-. is slidingly mounted on this, upper end the post 5|. "The runner 53, on its face toward the pressermemher 6, carries afstu d 54 which pivotally mounts a link 55. The link55 is confined on the; stud 54 in any. suitable manner, such as by a nut 56 which is threaded upon a reduced end of the stud 54. The engagement of this nut against av shoulder on the stud 54 prevents tightening of the nut 56 sufficiently to retard free, pivotal movements of'link55. Thelink 55depends from the stud 54 and at its lower end itslidingly re-, ceives a rod 51 which is secured thereon in. dif.-' ferent positions by a set screw 58.. The lower end of the rod 51 is bent laterally as at 59' to ex-.. tend toward the member 8. The cam 40 is. provided with a notch or recess 50 (Figs. 1 and 9) in the face towards themember 38 andin its upper surface, for approximately.- the eircu m. ference thereofiand the lowerend ofthe rod 51 is received in this notch60, so that the bent, or angular end 5.9 may enter thepassage 43 and be confined therein by member. 3 "This. end 59 rides freelyin thepassage- 43, and the; lower surface 6| (Fig, 9); of theang ular end 55 is; V-shaped WW W QHt 0 .13 fi in the throat p1 & c t er of. a e. two shrine b l catch. un ts 62. ar an ed one. a v he othe a d ach unit has. a ball 6 which u ed utwardly partly out. of a shell or casing 64 by a springv 65. These spring al ca che a w k wn in th a a d may ward movementon post 5|, it will be held against do eent as t e. ba l b t e r si ance o th a s t m a reinwardla, t e e ht at h run a d. t lin and r 51 carried ther in s ioi nt. o or he run eras t e a ls Wh n. e unner 3 is bel w o o the ba s 63 h e. t alls fre y unde th act o gra t Q lr o h l ca h s n ces ar but th use of is. more ce tain to p e en a rdental release. of 2 3 1 3 S Q 5 Q1 head ne th the bl ck 0- n Zi im t e mo ments of these blocks under the urging of springs 24 and 28.

In the use of this apparatus the superposed layers of fabric to be united (designated F collectively) are disposed beneath the; presser foot (Figs 6 n an o r. th th o t la e. as usual in sewing machines, The lower thread 66 which is carried by a bobbin (not. shown) beneath e. ro at as. us a in ewi g machines is 1 1 4 QRWWdlX hrou h. h th oat ate. The. upper thread 6'! supplied from a spool on the sewing head, after pass n th ug t e, us a hr a te ionins meansinot shown),,is threaded through the. eye 5 i h nee 3 a sua o e a aohi os- In a w ora oainit a d heua an e the lower or pointed end of the needle 3 pierces the fabricv layers to, carry the eye 5 and upper thread 61 beneath the fabric layers and there he p r rea n or nsa dth h lower h ad 66 as. s al in so -ins. maoh li ss t e n e 3 s w thdrawn. from. the. ia yers the h ad s pul d urwar lr and ten: sioned. While the needle. is elevated the dogs l5 are operated in a manner usual in sewing machines to feed the fabric layers E to the left i s? a d 6, adisiaees ua to a; d sired length of stitch, which length may be varied by th sua flo n me anism un on se in machines. The upper thread 61. is then in the position shown in Figs. 6 to 8..

Du i s. us a sa in perat on u t scribed, the additional ineehanism constructed in accordance with. this invention is effectivev to alternately project the fingers 22 and 23. beneath the upper thread 67 leading to the needle from the fabric so that whenever the needle descendsv for anew stitch, one of the fingers22 or 2,? Wiil bev beneath the upper thread 67' of that stitch, as shown by the finger 22 in Figs 6 and 7. When t e. n edle. desce s. or. ext t t h h other finger 23 will move beneath that portion of the thread 61 which extends from the fabric to the eye of the needle, a manner to be explained presently, and as finger 23 moves beneath the thread 67 and across the slot l2 in the presser foot, the finger 22- will be removed from beneath the upper thread 61 of the previously completed: stitch, and then moved forwardly ready-. toagain more beneath the thread- Qisaossdaa ona hanosti it. E125... land; 2; z; ulimthenest following-stitch;

To alternately place the fingers 22 and 23 under the thread of successive stitches in this manner, and then remove them after the stitches have been completed, provision is made to rock the head ll alternately back and forth, as will now be explained. As the needle bar 2 ascends into the position shown in Fig. 1 at the end of a stitch formation, it carries with it the bar 46 and post During the stitch formation the runner 53 is above the spring balls 63 as will appear later, so that as the post 5| rises it will carry with it the runner 53, the link 55 and the depending rod 51. During this ascent, when the angular end 59 on the lower end of rod 51 engages the arcuate surface of the passage -43 in cam 40 as shown in Figs. 1, 2 and 3, the rod 51 is held against further ascent and through the link 55 the runner'53 is held against further ascent. The post 5| continues to rise, however, and the runner 53, which is held, then is relatively forced past the balls 63, during which the balls are pressed inwardly, and as soon as the runner 53 clears the lower ball 63 it falls, carrying with it the link 55 and rod 51. The cam 40 when idle always remains in either the Fig. 4 or Fig. 5 position, because of stop edges 36 and 31 and the weight of runner 53.

Assuming that cam 40 is in the position shown in Fig. 4, it will be observed that as the rod 51 rises, the angular end 59 will ride along one side of the V-shaped surface 45, pass the apex of the V wall, and then swing by gravity, aided by the camming action of the arcuate wall of the passage 43, into a vertical position, slightly to the right of the apex of the wall 45, so that when the runner 53 is released from the lowermost ball 53, as just explained, and falls, the angular end 59 will pass to the right of the apex of wall 45 and ride down the opposite wall of the V, engaging in the right hand terminus of the passage 43. Thereupon' the weight exerted on this right hand terminus by the runner 53 and link 55, will rock the cam 40 through the intermediate position shown in Figs. 1, 2 and 3 from the extreme position shown in Fig. 4 to the other extreme position shown in Fig. 5. Engagement of head H with edges and 31 limits rocking movements of shaft l6 and cam 40.

The cam rocking in this manner also rocks shaft Hi, to which it is coupled by member 38, through a corresponding angle (clock-wise in Fig. 7) and this movement moves the finger 23 beneath the thread 61 and across the slot |2 in the presser foot. By this same movement the finger 22 is removed from beneath a completed stitch. During this movement of cam 40 the ball 34 moves out of contact with the beveled face 30 on the block 2|, so that the finger '23 may move downwardly, under the urging of the spring 28, into a position across and over the slot l2, and then when the needle next descends, the thread Bl will be pulled downwardly over the finger 23. During this same rocking movement of the shaft I6 the beveled cam face 29, moves beneath the ball 34 and since the cam face 29 is above the pintle H), the block 20 will be rocked on the pintle IS in a direction to carry the finger 22, which is then clear of the previously completed stitch, in a direction to move the finger 22 forwardly, immediately at the rear and one side of the needle, and ready to move beneath the thread 61 as soon as the needle again rises and the shaft I6 is rocked back into its former position which is represented by the position of the cam 40 in Fig. 4.

While the finger 23 is across the slot I2 of the presser foot, the needle again descends and pierces the fabric, the upper and lower threads again are interlocked, and then the needle rises and tensions the upper thread. During this operation, the finger 23 is stitched to the fabric, but during the next stitch forming operation the finger 23 is withdrawn, which leaves a slack in the thread of the completed stitch, as shown in Fig. 6. During each descent of the needle 3, the arm 46 is also carried downwardly, but since the runner 53 is limited in its downward movement by the engagement of the angular end 59 with the right hand terminus of the-cam in Fig. 5, the post 5| during its descent will carry its balls 53 below the runner 53. Thereafter when the needle again rises the balls 63 will engage with the lower edge of the runner and move the runner with the post 5| thus raising the rod 51.

As rod 5'! rises, the lower angular end 59 will ride along one side of the V-shaped wall 45, and then will be swung to the left in Fig. 5 by gravity 1 and the camming action of the arcuate surface defining the upper limit of the passage 43, but when the passage 43 limits further upward movement of rod 51, the continued movement of post 5| with the needle bar will cause the balls 63 to pass above the runner 53. The runner then immediately falls by gravity, and during its descent the angular end 59 at the lower end of the rod 51 will engage with the other side of the V-shaped wall and be cammed thereby to the left into' engagement with left hand terminus of the pas-' sage 43. The inertia and weight of the runner 53, link and rod 51 will then rock the cam 40 from the Fig. 5 to the Fig. 4 position, during which the cam 40 passes through the intermediate position shown in Figs. 1, 2 and 3. v

This movement rotates the shaft l6 back into its former position shown in Figs. 6, 7, and 8, during which finger 23 is removed from beneath a completed stitch and moved forwardly by the ball 34, ready for movement beneath the thread 61. Atthe same time finger 22 is moved beneath the thread 5! and downwardly over the slot I2, so that when the needle 3 next descends, the finger 22 will be sewed against the superposed layers of the fabric as shown in Figs. 6, 7 and 8. Thus this cycle will be repeated over and over until the row of stitching is completed.

It will be noted that while each stitch is being formed there will be a finger 22 or 23 secured beneath the upper thread 61 and against the upper face of the superposed fabric layers, and thenafter the thread has been tightened the finger is removed from beneath the completed stitch, which provides a desired degree of slack ness in the thread of the completed line of sewing or stitching. In this manner the sewing may proceed at the usual rate during which the upper thread 6'! is tightened, yet, as the fingers are removed from beneath the thread, a small amount of slackness will be left in the stitch thread. Thereafter when the sewed fabrics or layers are washed the shrinkage of the thread will not cause a further shrinkage of the fabric or a puckering thereof. It will also be observed that this improved and added mechanism will operate in the same manner, even though the length of the stitch is varied by varying the extent of the usualfeeding mechanism of sewing machines.

It will be understood that in Fig. 6 the presser foot is not shown, in order that'the-slackness in -the completed stitching and the position of the finger 22 may be seen. It will also be understood 1. In a sewing machine of the type having a throat plate, a feed dog operating upwardly through said plate to feed the work over said plate by increments, a pressure foot, a head, a needle, a bar mounting said needle and means operating said needle bar and needle vertically in timed relation to the movement of said dog to sew, that improvement which comprises a finger disposed with its free end above and across the line of stitching immediately in the rear of the needle, a member mountingsaid finger for limited movement in directions sidewise of said line of stitching to carry the free end. of said finger back and forth across the axis of the line of stitching in proximity to the work on said throat plate and also for movement in the direction of feed, and an operating connection from the neodl'e operating means to said member for moving the free end of said finger across said line of stitching at the rear of the needle beneath the thread from the needle to the work, and remov ing it from beneath the thread during the formation of another stitch.

2. In a sewing machine of the typehaving a throat plate, a presser foot for confining work to said plate, a needle which reciprocates vertically and carries a thread through the work step by step, means for reciprocating the needle end wise, and a feed dog operating upwardly through said plate for feeding the work along by incre ments after each piercing of the work by the needle and its thread, that improvement which comprises a finger having a free end disposed at the rear of the needle and beneath the thread from the needle to the workgeneraHy' parallel to the face of said plate and crosswise of the direction of feed of the work, a support mounting said finger for movement back and forth in the direction of the line of feed, a member mounting said support for rocking movement in a direction crosswise of the line of feed to carry the free end of the finger back and forth acrossand in close proximity to the line of feed, an operative connection from said needle-reciprocating means to said mounting for rocking the iatt'erin: a direction crosswise of the line of feed in one direction only at each complete reciprocation of the needle, and an element acting, on said support, as the support rocks to remove said free end of said finger from across the line of feed, for positively moving said freev end forwardly towards said needle and for releasing it when it rocks the opposite direction, whereby when said member is rocked in one direction to carry the. free end of the finger, across the feed line said finger will be sewed by said thread to the. work, and

when said member is rocked in the opposite: di-

' rection from across the feed line, said finger will be withdrawn from beneath the. thread of the 1.0 completed stitch to leave slacls in the thread of the completed stitch from which it is withdrawn.

3. In the method of uniting layers of fabrics by the usual stitching, in which a thread is passed through the superposed fabrics at spaced intervals by a needle and the: fabrics moved beneath the needle by increments while the needle is withdrawn from the fabric, that improvement therein for providing selected slackness in the thread of the uniting stitch, which comprises the steps, during the sewing, of placing an individual interponent at intervals beneath the thread section extending from the fabric to the needle while the needle isabove the fabric and before the: needle again enters the fabric, continuing the sewing with the interponent so placed to sewthe interponent to the fabric, feeding the fabric with the engaged interponent in a feeding direction ready for another stitch formation, and withdrawing the intersonent from beneath the thread in the stitch after the stitch has been completed, and during the formationof another stitch.

4. In the method of uniting layers of fabrics by the usual stitching, which a thread is passed through the superposed fabrics at spaced intervals by aneedle and the fabrics moved beneath the needle' by increments while the needle is withdrawn from the fabric, that improvement therein for providing selected slackness in the thread of the uniting stitch, which comprises the step, during the sewing, of placing a plurality of individual interponents, in succession beneath that portion of the thread extending from the fabric to the needle while the needle is away from the fabric before the needle again enters the fabric, sewing the interponents in alternate succession to the fabric, moving the interponents with the moving fabric to which stitched, in a feeding direction and Withdrawing each interponent insimilar succession from beneath the thread of the completed stitch, while another interponent is being sewed to the fabric.

5. In the method of uniting layers of fabrics by the usual stitching, in which a thread is passed through the superposed fabrics at spaced intervals by a needle and the fabrics moved beneath the needle by increments while the needle is withdrawn from the fabric, that improvement therein for providing selected slackness in the thread of the uniting stitch, which comprises the steps of sewing to the: fabric on the exposed face thereof, by the. needle and the thread which unites the fabric layers and in the same operation, a plurality of individual interponents, one beneath each of selected stitch loops in succession, and pulling the interponents in the same succession from beneath the. stitching completed thereover, during subsequent sewing operations.

6. In themethod of uniting layers of fabrics by the usual stitching, in which a thread is passed through the superposed fabrics at spaced intervals by a needle and the fabrics moved beneath the needle by increments while the needle is withdrawn from the fabric, that improvement therein for providing selected slackness in the thread of the uniting stitch, which comprises the steps of inserting individual interponents beneath that portion. of the thread extending from a completed stitch to the needle while the needle is disengaged from the fabric, alternately" from opposite sides of the line of stitching, sewing the interponents so positioned in succession to the fabric with a single interponent beneath each thread loop of a stitch moving each interponent with the fabric to which 11 it is sewed, and pulling the interponents from beneath the stitching completed thereover, in the same succession but alternately from opposite sides of the line of stitching, during an operation of the needle subsequent to that which sewed that interponent to the fabric.

7. In the method of uniting layers of fabrics by the usual stitching, in which a thread is passed through the superposed fabrics at spaced intervals by a needle and the fabrics moved beneath the needle by increments while the needle is withdrawn from the fabric, that improvement therein for providing selected slackness in the thread of the uniting stitch, which comprises the steps of stitching separate fingers to the fabric layers in succession by the same thread and operation that unites said fabric layers, moving the fingers with the fabric portion to which they are sewed during the feeding operations of the fabric, and then removing said fingers from beneath the thread of the stitching after the needle has started its descent to sew another finger to the fabric to leave slack in that thread of the completed stitch.

8. In the method of uniting layers of fabrics by sewing in which a thread is carried through the superposed fabrics at spaced intervals and the fabrics moved beneath the needle between suc cessive needle movements through the fabrics and while the needle is clear of the fabrics, that improvement therein for providing selected slackness in the thread of the uniting stitch so formed, which comprises confining a finger-like interponent repeatedly to the fabrics by a thread in the same sewing operation and by the same thread that unites the fabrics, with the thread passing through the fabrics at the sides of and free of the interponent, and withdrawing the finger from beneath each finger-confining stitch after formation of at least one subsequent stitch has started.

9. In a sewing machine of the type having a throat plate, a presser foot for confining work to said plate, a needle which reciprocates vertically and carries a thread through the work step by step, means for reciprocating the needle endwise, and a feed dog operating upwardly through said plate for feeding the work along by increments after each piercing of the work by the needle and its thread, that improvement which comprises a finger having a free end disposed to extend approximately crosswise of and in proximity to the line of sewing and immediately in the rear of the needle, means mounting said finger for movement in a direction to carry its free end crosswise-of said line of sewing between one posi= tion at one side of said line and another position across said line, and also for limited movement in a direction back and forth along said line be tween one position in which said free end is beneath the position of the sewing thread extending from a completed stitch to said needle while the needle is withdrawn from the work, and means operated in timed relation to the needle movements for moving said finger to carry its free end crosswise of said line of sewing to a position at one side of said line when said needle is away from said work in one operation and back into a position across said line when the needle is away from said work in another operation, repeatedly, and means urging said free end of said finger towards said needle when it is at said one side of said line of sewing, in a position to move beneath the sewing thread when it is again moved into its position across said line of sewing 10. In a sewing machine of the type havin & throat plate, a feed dog operating upwardly through said plate,

a head, a pressure foot, a needle bar, and a needle carried by said bar and reciprocated vertically thereby in synchronized relation to the movements of said feed dog, that improvement which comprises a member mounted to rock about an axis generally parallel to the di rection of feed of fabric by said dog, also to swing about an axis crosswise of said direction of feed, and having a projecting finger disposed just above the pressure foot and adjacent said needle, said finger being movable, during its rocking with said member, between the thread and needle while the needle is above the fabric, remaining in that position while the needle descends and a stitch is formed over said finger, and moving along the line of sewing with the work through rocking of said member on said crosswise axis, and means operated in timed relation to the movements of the needle for rocking said member about said axis parallel to the .direction of feed to carry said finger from beneath the stitch formed thereover, said member being yieldingly urged towards the needle about said crosswise axis when pulled from .beneath said stitch.

11. In a sewing machine of the type having a throat plate, a needle, and means for feeding fabrics to be sewed together step by step be neath the needle while the needle is above the throat plate, that improvement which comprises a finger having a free end extending crosswise of the direction of the feed of the fabrics at the rear of the needle, means mounting said finger for movement of its said free end into and out of a position across the fabrics at the rear of the needle and beneath the thread passing from the last formed stitch to the needle and also for movement in the direction of the line of feed of the fabrics, whereby when said finger is in its said position said finger will be sewed to the fabrics and then may move with the fabrics alon said line of feed, and means operable in timed relation to the movement of said needle for moving said finger endwise beneath the thread from said fabrics to the needle during the formation of a stitch, and then removing it endwise from beneath the thread of the stitch after the stitch has been completed and fully tightened, so as to leave slack in the thread of a completed stitch.

12. In a sewing machine of the type having a throat plate, feeding means for feeding super posed fabric layers to be sewed together across the throat plate, a needle disposed above said throat plate and fabric, and operable through the fabric and backwar'dly for carrying a thread through the fabric for interconnection with a lower thread, that improvement for causing slack to be formed in the thread of any completed stitch which comprises a finger having its free end extending generally in a direction crosswise of the direction. of feed of the fabric layers, means mounting said finger for movement in said crosswisedirection, and also in the direction of feed of the fabrics, means for interposing said finger between said layers and a thread of said stitch during the'formation of that stitch, and then removing it from between the thread and fabric after that stitch has been completed and has moved the finger along said direction of feed with the fabrics, said means being operated in timed relation to the movement of saidneedle.

13. In a sewing machine of the type having a throat plate,'feeding-' means for feedingsuperposedfabric layers to be sewed together across the throat'plate, a needle disposed above said throat plate and fabric, and operable through the fabric and backwardly for carrying a thread tnrqugn the fabric for interconnection with a lower thread, that improvement for causing slack to. be formed in the thread of anycompleted stitch which, comprises a finger having its free end extending. generally in a direction crosswise. of the direction of feed of the fabric layers, means mounting said finger for movement backand forth across the line of sewing, immediately in the rear of the needle and also for, movement with the. fabrics by said feeding; means, and means for operating said needle and said finger in timed relation to, each, other, and for interposi'ng said. finger between said layers and a thread of said stitch during the formation or that stitch, and then removing it from between the thread and fabric after that stitch has been completed and has been moved with said fabrics in a feeding operation, and, while said needle withdrawn from said fabric.

14 In asewing machine of the type having athroat plate, feeding means for feeding super posed fabric layers to be: sewed together across the throat plate, a needle disposed above said throat plate andv fabric, and operable through the fabric and backwardly for carryinga thread through the fabricf'c'r interconnection with a lower thread, that improvement for causing slack to be iormedin the thread of. any completed stitch which comprises a pair of fingers having free ends extending towards each other from opposite sides of the line of sewing, andma direction crosswise of the direction of the feed of the fabric layersbeneaththe needle; mean-s mountingsaid fingers for movement to carry said free ends alternately across the line of sewing and between the fabric and a thread of the stitch, during the formation of that stitch, so that the fingers may be alternately and successively sewed to the fabric by the thread, whereby when either finger is interposed between a thread and the fabric layers in the formation of a stitch, the other finger will be removed from between the fabric and the thread of a completed stitch to provide slackness in the thread of the completed stitch, and means for moving said fingers back and forth in timed relation to the movement of said needle.

15. The method of sewing fabric plies to prevent subsequent puckering and compression of the sewed plies by the shrinkage of the thread when the sewed plies are laundered, which comprises progressively sewing the fabric plies, feeding them along step by step, and concurrently during the sewing, disposing interponents in succession upon the fabrics beneath the thread that unites the fabric plies so that the interponents will be confined to the plies and move with them during their feeding movements, and removing the sewed interponents from completed stitches in'similar succession during the samesewing operation in the formation of another subsequent stitch by the same thread.

15. In a sewing machine of the type having a throat plate, a presser foot for confining work to said plate, a needle which reciprocates vertically and carries a thread through the work step by step, means for reciprocating the needle endwise, and a feed dog operating upwardly through said plate for feeding the work along by increments after each piercing of the work by the needle and its thread, that improvement which comprises a finger having a free end disposed to extend approximately crosswise of and in proximity to the line of sewing and immediately in the Q'rear of the needle, means mounting said finger for movement in a direction to carry its free end crosswise of said line of sewing between one position at one r in side of said the and another position acrosssaid line, and also for llmitfedmovemcnt in a direction back' and forth along" said line between one position in which said free end is beneath the position of the sewing thread extending from a completed stitch to said needle while the needle is withdrawn from the work, and means operated in timed relation to the needle movements for moving said finger to carry its free end crosswise of said line of sewing to a position at one side of saidline when saidneedle is away from said work in one operation and: back into a position across saidli-ne' when the needle is away from said work in another operation repeatedly.

17. In a sewing machine of the type having a throat plate, a feed dog operating upwardly throughsaid plate for feeding, step by step, a fabric resting thereon, a head, a pressure foot, a. needle barreciprocating vertically in a synchronized relation to the movement of said feed dog, and a needle carried by said bar, that improvement which comprises a shaft carried by said pressure foot and extending in the direction parallel to the direction. of the feed of thefabric by said feed dog, a pair of arms hinged on the end of: the shaft nearest the needle for rocking movement with theshaftabout the shaft axis and also for individual rocking on said shaft about an axis disposed in a plane transverse to the axis of; said; shaft, a finger" carried by the lowerend of; each arm andextending toward the finger on theother arm, so that as the shaft is rocked the free ends of the fingers will be carried alternately back and forth across the direction of feed travel of the fabric and in close proximity to any fabric on said throat plate in feeding position, said fingers being disposed at one side of the needle and movable, by rocking of the shaft, alternately into and out of positions beneath a thread leaving the last formed stitch and the needle, a member on the pressure foot for engaging with said arm alternately when said shaft is rocked and camming said arms in directions to carry the fingers alternately towards the needle path, each finger being cammed towards the needle when its free end is furthest from the line of stitching, and released when the finger is moved, by rocking of the shaft, across the line of stitching, and an operating connection from said reciprocating needle to said shaft for rocking said shaft alternately in opposite directions to place said fingers alternately across the line of stitching.

18. In a sewing machine of the type having a throat plate, a feed dog operating upwardly through said plate for feeding, step by step, a fabric resting thereon, a head, a pressure foot, a needle bar reciprocating vertically in a synchronized relation to the movement of said feed dog, and a needle carried by said bar, that improvement which comprises a shaft carried by said pressure foot and extending in the direction parallel to the direction of the feed of the fabric by said feed dog, a pair of arms hinged on the end of the shaft nearest the needle for rocking movement with the shaft about the shaft axis and also for individual rocking on said shaft about an axis disposed in a plane transverse to the axis of said shaft, a finger carried by the lower end of each arm and extending toward the finger on the other arm, so that as the shaft is rocked the free ends of the fingers will be carried alternately back and forth across the direction of feed travel of the fabric and in close proximity to any fabric on said throat plate in feeding position, said fingers being disposed at. one side of the needle and movable, by rocking of the shaft, alternately into and out of positions beneath a thread leaving the last formed stitch and the needle, a memberon thepressure foot for engaging with said arms alternately when said shaft is rocked and camming said arms in directions to carry the fingers alternately towards the needle path, each finger being cammed towards the needle when its free end is'furthest from the line of stitching, and released when the finger is moved, by rocking of the shaft, across the line of stitching, a member fixed on said shaft and having therein a cam groove extending partly around the axis of the shaft, the inner surface of the groove between its ends being approximately V shaped, a shoe, a link hinged to said shoe for'rocking on a horizontal axis, depending from the shoe and having a lateral terminal at its lower end running in said groove, and means coupling the needle bar and shoe for lifting the shoe each time the needle is lifted and then dropping it.

19. In a sewing machine of theltype having-a throat plate, a feed dog operating upwardly through said plate, a head, a pressure foot, a vertically reciprocating needle bar operating in a synchronized relation to the movements of said feed dog, and a sewing needle carried by said bar, that improvement comprising a shaft rockably mounted on said pressure foot and having at one end a cam groove extending part way around the rocking axis of the shaft, the inner wall of said groove between its ends being generally V- 16 shaped, an upright member coupled to said needle bar for reciprocation therewith, a shoe slideable upon said reciprocating member, a link hinged to said shoe on a horizontal axis, depending from the shoe, and having a horizontally extending terminal at its lower end, said terminal running freely in said cam grooveso that as the shoe is raised and lowered, said terminal will engage alternately with opposite ends of said groove and rock the feed shaft alternately in opposite directions, a coupling between said upright member. and shoe for connecting them, for movement together with the needle bar, when the latter is in its lowermost position, and for lifting of the shoe during ascent of the needle and dropping it before the needle bar completes its upward travel, and means also carried by the shaft for alternately interposing a pair of fingers beneath the thread in the formation of a stitch and removing one finger when the other finger is inserted beneath the thread.

THOMAS A. BRAMFITT. EDWARD C. PFEFFER, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Lutz Sept. 17, 1935 

